Full Name: Takuya Kai
Warrior Designation: Blue Beet, Super Blue Beet
Weapons: Saber Magnum, Stinger Blade, Stinger, Drill and Beet Ingram
Gear: B-Commander
Beet Machine: Beetluder, Mega Heraclesr

Kai Takuya is 23-year old insect researcher at the Earth Academia. He is the first to meet Guru in the South American rainforest, he was also the first to gain a B-Commander and use his suit. As BlueBeet and leader of the team, his armor was modeled after a kabutomushi (helmet beetle). A blood sample from Kai was used by the evil sorcerer Jagui in the creation of his evil clone Shadow with the help of a Kamikirimushi (long-horned beetle). Blue Beet's Beet Machine is the Beetluder.

In episode 36, Blue Beet gained the ability to evolves into Super Blue Beet, with four metallic insectoid wings extending from his back and Plasma Dischargers, growing from his wrists and ankles. He transforms to Super Blue Beet with the command "Metarufooze!" (Metal-Phose), and in this mode he can employ the full power of the Beet Ingram. Energy is collected in his wings and is then transferred to the Beet Ingram Final Mode, releasing the Super Final Blow.